During 2014 alone, the inflow of black money was about $101 billion while the outflow was $23 billion, it said.

Titled 'Illicit Financial Flows to and from Developing Countries: 2005-2014', the report released Monday is the first global study to place equal emphasis on illicit outflows and inflows.

The findings assume significance as India has no official assessment on the quantum of black money in the country and abroad.

The illicit financial inflow of $770 billion was 14 per cent of India's total trade of $5,500,744 million ($5,500 billion), GFI said.

It pegged the inflow of black money at three per cent (about $165 billion) of the country's total trade during the 10-year period.

The volume of global illicit flows is staggering, ranging between $2 trillion and $3.5 trillion in 2014, the report said.

"Estimated illicit outflows from developing countries to the advanced world alone sum up to $620 billion in 2014 in the most conservative calculation and illicit inflows from the advanced countries into the developing world totalled more than $2.5 trillion."

From Asia, the study estimated financial inflows to developing countries from a minimum of $686 billion to a maximum of $1,229 billion.

One dominant channel for illicit financial flow (IFF) moving in and out of the developing world is trade mis-invoicing, it said, adding that trade mis-invoicing accounted for at least 66 per cent of measurable IFF outflows and 97 per cent of measurable inflows in 2014.

Trade mis-invoicing is a form of trade-based money laundering made possible by the fact that trading partners write their own trade documents or arrange to have the documents prepared in a third country (typically a tax haven), a method known as re-invoicing.

"Fraudulent manipulation of the price, quantity, or quality of a good or service on an invoice allows criminals, corrupt government officials, and commercial tax evaders to shift vast amounts of money across international borders quickly, easily, and nearly always undetected," the report said.

Suggesting steps to check black money, the financial watchdog said governments should establish public registries of verified beneficial ownership information on all legal entities to check black money.

"All banks should know the true beneficial owner(s) of any account in their financial institution."